UKC

Sorry for the long post but I am at my wits end on this one.

I live on hill. If I walk out of my back door I am on a raised patio (about 12 foot above the garden) looking out over the goyt valley. Below the patio is an old out house. It looks out on to the garden @ ground level. It backs up against soil & the house foundation. On one side of the outhouse is my neighbours outhouse. On the other is an old coal bunker room.

About three years ago I turned the outhouse into a bouldering room. I started by digging the floor out (by about 2 feet), laying a vasquine sheet & then a 3 inch concrete slab on top of this. Around the back & side walls I attached 3 wooden beams to the concrete slab from which the rest of the bouldering wall structure was screwed.

My problem is that during heavy periods of rain water seeps in from under the wooden beam that is on the wall next to the coal bunker room.

I looked behind the hold panels but the area above the wooden beams next to the wall is dry.

My dad figured this was due to the water table & the fact the soil floor in the coal bunker is higher than the climbing room floor. So he got me to dig a sump last autumn in the coal bunker. I dug it to about 3 feet deep. Throughout the winter the room was bone dry & I thought I'd cracked it. Though I did wonder why I never needed to pump the sump out. However since late spring this year the water is back & since autumn it is really bad, to the point I cannot really use the room.

My dad now rekons I need to dig the sump deeper & try to dig under the wall below the climbing room floor, being careful not to damage the vasquene sheet. He believes the high water table is very local & doing this will allow it to drain into the sump.

Do any of you have any ideas?

In reply to leon:

Seem to remember seeing warnings about digging deeply into the ground without any supports for the earth, think it was about accidents in the construction industry. I don't know how deeply deep enough to need to take precautions is though.

No idea about anything else. I'm wondering does your dad have a secret plan for the hole? ()

In reply to leon:

Do not enter a non-reinforced pit of more than 1 metre deep. You can die, and people have.

http://www.ags.org.uk/site/newsletters/nlnov08.cfm#alert

In reply to leon:

Does the sump you dug have a drain? If not, isn't it simply going to fill with water up to the level of the water table, and then you have the same problem? Or are you assuming the sump will drain into the surrounding earth (sounds like that's the plan your Dad is suggesting by digging under the floor)? What's ground type? Are you hitting impermeable bedrock or clay (i.e. so the sump cannot drain)?

I take it you meant 'visqueen', since google doesn't find much relevant for 'vasquine'...

http://www.visqueenbuilding.co.uk/

Maybe one of their tanking membranes might be the answer, but that might involve digging out the entire space behind the wall, applying the membrane, and then back-filling.

http://www.visqueenbuilding.co.uk/tanking

ps. I'm just working from the basic principles of the problem, not from any professional or personal experience, since replies seemed rather sparse...

In reply to leon:

Do any of you have any ideas?

Yes, let nature take it's course and have an indoor deep water soloing venue.

In reply to MJ: Or wait for it to freeze in the coming months and have an indoor ice wall

In reply to leon:

A submersible pump and float switch in the sump?

In reply to leon:
I have a spring under my house. To stop is rising above the basement floor which is built about 2 feet above bedrock, I have a sump pump. This pumps water out when it detects water into the storm drain.

In reply to leon: sounds like. as said above u need to tank the outside wall. big job by the sounds of it. your sump/sokeaway is too small to. and if like u think your in the water table it Will never be big enough. Not sure if u have a storm line anywhere lower down the garden u could run a pipe to from your sump. but tanking the wall Will sort it out if done rite....

In reply to leon:
It would be more like puddle splashing than DWS.

I have a sump pump but the water level in the sump is always below the floor on the other room!!

The ground is a clay soil.

When we were digging the floor out my dad said he noticed water collecting in the two areas I now have the leak. I've read that the water table is not at the same level everywhere. Hence my dad thinking that if I dig under the water to where the water was pooling it might draw the water into the sump.

In reply to leon:
I suspect tanking out the wall will mean ripping out the climbing wall & taking the concrete floor up. I think I have to try other less drastic options first.